Over on DF we have a thread asking about should a monk's disease immunity (or paladins) make him immune to becoming a lycanthropy if he's damaged enough in battle? What about mummy rot, green slime, other types of mold/magical diseases??

So the paladin's ability (power) to cure disease would not have any effect on lycanthropy. Neither would the paladin's or the monk's immunity to disease prevent it since it's not a disease.

It further says:

"While often considered a disease, lycanthropy can more properly be described as a natural condition, in some cases, or a curse, in others."- 2E DMG, pg. 131

Summarized, true lycanthropes are able to change form at will (which is a natural condition) while those who are afflicted by a werewolf (for example) and become lycanthropes would be considered under a powerful curse.

Finally, I'm not even sure why anyone would ask this particular question, because the PHB clearly states:

"A paladin is immune to all forms of disease. (Note that certain magical afflictions - lycanthropy and mummy rot - are curses and not diseases.)"- 2E PHB, pg. 27

It's like...read the books people. But then again, we are talking about Dragonsfoot!

Mummy rot is a bit different. Mummy rot isn't so much a disease as it is a type of damage generated from the mummy's connection to the Negative Material Plane.

[Note: Yeah, yeah, the error of linking the mummy to the Positive Material Plane has been "accepted" for decades, despite the fact that Gygax claimed it was a typo and despite the fact that it makes no sense within context of the game. They're linked to the NEGATIVE Material Plane. Consider the gauntlet flung if anyone wants to go there. ]

I like how it was explained in Van Richten's Guide to the Ancient Dead. Something along the lines of the energy from the Negative Material Plane (I'm correcting the repeated mistake in that resource where it lists the Positive Material Plane - just play along... ) inflicts a corrupting damage that rots the flesh. I never liked the fact that cure disease cured mummy rot. But then again, it could be explained as simply a disease similar to leprosy that comes from being touched by a being who's been dead for centuries and is covered in disease-ridden bandages. That being said, if a cure disease spell can cure mummy rot, then so should the paladin's ability to cure disease. The immunity to disease that the paladin and monk share would also be effective in this case.

Green slime is an odd case. Most slimes/oozes/jellies dissolve things. The only difference with green slime is that it not only dissolves metal or wood, it actually converts flesh into green slime as it dissolves that flesh. The fact that a cure disease spell kills green slime doesn't imply that an immunity to disease would protect a person from the effects of the slime. I don't see how the attack of a slime can be considered a "disease". So I'd say no, the immunity doesn't apply. Same for molds and magical diseases.

Well it might cause the editions views on them ARE different. 2e did clarify it, and that's something i pointed out on DF.. However, in a purely 1e game, the DMG and PHB are silent on whether it is or is not a valid PoV that being immune to disease also means being immune to contracting lycanthropy..

Yeah, 1E was far more vague on the issue. I still ran it the same way though. If you look at all the rules for lycanthropy in the 1E DMG, like the part where a character can spend a month in a monastery drinking holy water and herbs twice a day, etc., it seems to me that lycanthropy was intended more as a special curse that required special steps to cure. So I've always considered it a curse, and therefore not affected by immunity to disease. I also always felt that took away the fun of it. There are so many ways to minimize or negate the chance of being 'infected' by lycanthropy. I'd hate to remove that fun by allowing immunity to disease to prevent it outright.